Solid powder pump pressurized entrained-flow bed gasification system and process

Abstract

The invention discloses a solid powder pump pressurized entrained-flow bed gasification system and process. The solid powder pump pressurized entrained-flow bed gasification system comprises a preparation unit, a solid powder pump and a gasification furnace. The preparation unit is used for preparing and storing powder, and the powder is stored in the form of a gas-solid mixture. The gasifier includes an inlet and an outlet. The solid powder pump is connected between the preparation unit and an inlet of the gasification furnace through a feeding channel and is used for continuously pressurizing and conveying powder of the preparation unit to the gasification furnace through the solid powder pump. The gasification furnace converts powder into crude synthesis gas through gasification reaction and discharges the crude synthesis gas from an outlet, compared with a traditional entrained-flow bed gasification system, the structure is simplified, tedious locking hopper pressurization and pressure relief operation steps of a powder conveying system are omitted, solid powder conveying continuity is guaranteed, the working efficiency of the entrained-flow bed gasification system is improved, and the entrained-flow bed gasification system is suitable for industrial production. And meanwhile, gas resources are saved.

Description

Technical Field

[0001] The present invention relates to the technical field of entrained flow gasification processes, and specifically relates to a pressurized entrained flow gasification system and process for solid powder pumps. Background Art

[0002] With the development of clean energy and green chemical technologies, gasification processes, as an important way for the efficient utilization of solid fuels such as coal and biomass, have received increasing attention. Entrained flow gasification has become the first choice for many industrial gasification applications due to its high reaction efficiency, good material mixing, and low operating temperature, and is widely used in fields such as chemical engineering, power generation, and city gas. However, there are still many technical bottlenecks in the transportation and pressurization of solid raw materials in existing entrained flow gasification processes, which limit the efficiency and flexibility of the gasification process.

[0003] In a traditional entrained flow gasification system, solid raw materials need to be sent into the gasification furnace through a pneumatic conveying system. The pneumatic conveying system usually includes an atmospheric pressure pulverized coal storage bin, a pulverized coal lock hopper, a feeding tank (discharging tank), etc. Its process flow is to send qualified pulverized coal from the pulverized coal preparation system into the atmospheric pressure pulverized coal storage bin through pneumatic conveying, send the pulverized coal in the atmospheric pressure pulverized coal storage bin into the feeding tank according to a certain sequence control process through the pulverized coal lock hopper, and send the pulverized coal into the gasification furnace to participate in the reaction by controlling the pressure difference between the feeding tank and the gasification furnace. The sequence control process of the pulverized coal lock hopper generally includes four cyclic steps: feeding, pressurization, discharging, and pressure relief. Specifically, first, the channel between the feeding tank and the pulverized coal lock hopper is closed. After the pulverized coal lock hopper is depressurized, the channel between the atmospheric pressure pulverized coal bin and the pulverized coal lock hopper is opened, and the pulverized material in the pulverized coal lock hopper is transported to the pulverized coal lock hopper by gravity. Then the channel between the atmospheric pressure pulverized coal bin and the pulverized coal lock hopper is closed, and the pulverized coal lock hopper is pressurized. After the internal pressure of the pulverized coal lock hopper meets the requirements, the channel between the pulverized coal lock hopper and the feeding tank is opened, and the solid pulverized material is pressed into the feeding tank by using the pressure difference between the pulverized coal lock hopper and the feeding tank. The pulverized coal lock hopper completes discharging, and then pressure relief is carried out according to the above steps, and thus the pneumatic conveying work of the solid pulverized material is completed in a cycle. It can be seen that the traditional entrained flow gasification system has a complex structure, the control steps of gas conveying pulverized materials are cumbersome, and the continuity of solid raw material transportation cannot be guaranteed, resulting in low working efficiency of the entrained flow gasification system and consuming a large amount of gas resources. More importantly, the traditional entrained flow gasification transportation method, that is, dense phase transportation, has a low transportation pressure, generally about 4.0 MPa, and has a high comprehensive energy consumption in most chemical processes with high pressure synthesis. Summary of the Invention

[0004] In view of this, the present invention provides a pressurized entrained flow gasification system and process for solid powder pumps, so as to solve the problems that the conventional entrained flow gasification system has a complex structure, the control steps of gas transporting powder are cumbersome, and the continuity of solid raw material transportation cannot be guaranteed, resulting in low working efficiency of the entrained flow gasification system and consuming a large amount of gas resources at the same time.

[0005] In the first aspect, the present invention provides a pressurized entrained flow gasification system for solid powder pumps, comprising:

[0006] A preparation unit for preparing and storing powder, wherein the powder is stored in the form of a gas-solid mixture;

[0007] An entrained flow gasifier, including an inlet and an outlet;

[0008] A solid powder pump, connected between the preparation unit and the inlet of the entrained flow gasifier through a feeding channel, and adapted to continuously transport the powder from the preparation unit to the entrained flow gasifier.

[0009] Optionally, the preparation unit includes a powder grinding device and a powder bin. The powder grinding device is communicated with the feeding port of the powder bin through a feeding channel, and the discharging port of the powder bin is communicated with the feeding channel. Among them, the powder prepared by the powder grinding device is transported to the feeding channel through gas.

[0010] Optionally, a second gas pipeline is provided at the discharging port of the powder bin, and the second gas pipeline is adapted to intermittently introduce loosening gas into the discharging port.

[0011] Optionally, a first gas pipeline is connected to the feeding channel to form a first node, and the first node is located between the solid powder pump and the entrained flow gasifier. The first gas pipeline is adapted to introduce high-pressure gas into the feeding channel.

[0012] Optionally, the gas introduced into the first gas pipeline and the second gas pipeline is one of nitrogen, carbon dioxide, carbon monoxide, hydrogen, methane, superheated steam, or a mixture of two or more of these gases.

[0013] Optionally, the inlet of the entrained flow gasifier is communicated with the feeding channel through a burner, and the burner is provided with a first feeding port and a second feeding port. The first feeding port is adapted to introduce spent fuel gas into the burner, and the second feeding port is adapted to introduce medium-pressure oxygen into the burner.

[0014] Optionally, it further includes a cooling unit and a washing unit, and the cooling unit and the washing unit are sequentially connected downstream of the outlet of the entrained flow gasifier.

[0015] Optionally, the washing unit is a washing tower, which is connected to the water inlet of the quench chamber of the gasifier through a first liquid supply pipeline, and a liquid pump is arranged on the first liquid supply pipeline.

[0016] Optionally, the cooling unit is a Venturi desuperheater. The water inlet port of the Venturi desuperheater is connected to the first liquid supply pipeline through a second liquid supply pipeline, and the connection point forms a second node. The liquid pump is located between the second node and the washing tower.

[0017] In a second aspect, the present invention provides a pressurized entrained flow gasification process for a solid powder pump, which is used for the above-mentioned pressurized entrained flow gasification system of a solid powder pump. The pressurized entrained flow gasification process for a solid powder pump includes:

[0018] A preparation unit prepares and stores powder;

[0019] A solid powder pump continuously pressurizes and conveys the powder in the preparation unit into the gasifier;

[0020] The gasifier converts the powder into raw syngas through a gasification reaction.

[0021] Advantageous effects:

[0022] 1. The pressurized entrained flow gasification system provided by the present invention includes: a preparation unit, a solid powder pump, and a gasifier. The preparation unit is used for preparing and storing powder, wherein the powder is stored in the form of a gas-solid mixture. The gasifier includes an inlet and an outlet. The solid powder pump is connected between the preparation unit and the inlet of the gasifier through a feeding channel, and is adapted to continuously convey the powder of the preparation unit into the gasifier.

[0023] In the present invention, the powder is stored in the form of a gas-solid mixture, so that the powder has fluidity. Then, the powder is continuously conveyed into the gasifier through the inlet by the downstream solid powder pump. The gasifier converts the powder into raw syngas through a gasification reaction and discharges it from the outlet. Compared with the traditional entrained flow gasification system, there is no need to set up a single or multiple feed hoppers, which simplifies the structure and also omits the cumbersome operation steps such as feeding, pressurizing, discharging, and depressurizing, ensuring the continuity of the solid raw material transportation, improving the working efficiency of the entrained flow gasification system, and saving gas resources at the same time.

[0024] Meanwhile, since the powder materials are stored in the preparation unit in the form of a gas-solid mixture, combined with the fluidity characteristic of the gas-solid mixture, the powder materials in the preparation unit can be transported to the gasifier for reaction in the form of dry powder dense-phase transportation through a solid powder pump. The solid powder pump can transport at a high pressure above 6.5 MPa and can also operate stably in high-temperature and high-pressure environments, ensuring the continuity, efficiency, and reliability of the transportation process. In addition, the feeding tank of the traditional entrained flow gasification system has the problem of uneven raw material supply, which leads to fluctuations in gasification efficiency or reaction interruption. In contrast, the method of transporting the gas-solid mixture through a solid powder pump can ensure that the gas-solid mixture enters the gasifier continuously, stably, and evenly, thus ensuring the stability of the gasification reaction.

[0025] 2. For the solid powder pump pressurized entrained flow gasification system provided by the present invention, the preparation unit includes a powder grinding device and a powder bin. The powder grinding device is connected to the feed port of the powder bin through a feeding channel, and the discharge port of the powder bin is connected to a feeding channel. Among them, the powder prepared by the powder grinding device is transported to the feeding channel through gas. The powder grinding device can grind solid raw materials into powder materials with a particle size meeting the requirements and transport the powder materials to the powder bin through the feeding channel in the form of gas transportation. Feeding through the gas transportation method can store the powder materials in the powder bin in the form of a gas-solid mixture, facilitating the subsequent transfer of the powder materials to the gasifier through a solid powder pump. Compared with the traditional elevator, conveyor belt, or hoist, such a setting not only simplifies the transportation structure between the powder grinding device and the powder bin but also can omit the subsequent step of converting the powder materials into a fluid gas-solid mixture.

[0026] 3. For the solid powder pump pressurized entrained flow gasification system provided by the present invention, a second gas pipeline is provided at the discharge port of the powder bin. The second gas pipeline is suitable for intermittently introducing loosening gas into the discharge port. Since the powder materials are stored in the powder bin in the form of a gas-solid mixture and the bottom of the powder bin is usually designed with a reduced opening, it is inevitable that powder caking or accumulation will occur at the discharge port at the bottom of the powder bin. Therefore, loosening gas, which refers to inert gas introduced into the discharge port, can be introduced into the discharge port through the second gas pipeline. The loosening gas can loosen the powder caking or accumulation at the discharge port or blow it to move along the side wall of the bottom of the powder bin, making the powder materials return to the state of a gas-solid mixture, preventing it from blocking the discharge port, and ensuring that the downstream solid powder pump can efficiently, continuously, and stably transport the powder materials to the gasifier.

[0027] 4. The pressurized entrained flow gasification system with a solid powder pump provided by the present invention is connected with a first gas pipeline on the feeding channel to form a first node, which is located between the solid powder pump and the gasifier. The first gas pipeline is suitable for introducing high-pressure gas into the feeding channel. When the powder leaves the solid powder pump in the form of a gas-solid mixture and enters the downstream, it can be mixed with the high-pressure gas and enter the gasifier together with the high-pressure gas. On the one hand, the high-pressure gas can further provide the conveying power. On the other hand, the high-pressure gas can be pressurized to ensure that the powder enters the gasifier under high pressure, further ensuring the continuous conveying of the powder and also ensuring the gasification efficiency of the powder in the reaction furnace.

[0028] 5. The pressurized entrained flow gasification system with a solid powder pump provided by the present invention has the inlet of the gasifier communicated with the feeding channel through a burner. The burner is provided with a first feeding port and a second feeding port. The first feeding port is suitable for introducing spent fuel gas into the burner, and the second feeding port is suitable for introducing medium-pressure oxygen into the burner. By respectively adding the spent fuel gas and the medium-pressure oxygen through the first feeding port and the second feeding port, the spent fuel gas and the medium-pressure oxygen can be mixed, and under the drive of the gas-solid mixture containing the powder, they can enter the reaction chamber of the gasifier at a high speed. Compared with directly introducing the spent fuel gas and the medium-pressure oxygen into the reaction chamber respectively, such a setting can ensure the uniform mixing of the spent fuel gas and the medium-pressure oxygen, provide oxidant and heat for the reaction in the reaction furnace, and promote the progress of the reaction in the reaction chamber.

[0029] 6. The pressurized entrained flow gasification system with a solid powder pump provided by the present invention includes a cooling unit and a washing unit, which are sequentially connected downstream of the outlet of the gasifier. The cooling unit can cool the raw syngas from the gasifier, and the cooled raw syngas enters the washing unit for washing to remove impurities, particulate matters and some acidic gases in the raw syngas. The finally output syngas can enter the subsequent chemical production or fuel utilization stage.

[0030] 7. In the pressurized entrained flow gasification system with a solid powder pump provided by the present invention, the washing unit is a washing tower, and the washing tower is communicated with the water inlet of the quench chamber of the gasifier through a first liquid supply pipeline, and a liquid pump is arranged on the first liquid supply pipeline. The washing tower removes impurities, particulate matters and some acidic gases in the raw syngas by spraying. The liquid that has washed the raw syngas can be pumped into the water inlet of the quench chamber of the gasifier through the liquid pump. The quench chamber drainage can cool the molten slag generated in the gasifier to form solid coarse slag, which is convenient for subsequent discharge treatment. By pumping the liquid washed in the washing tower into the quench chamber through the liquid pump, the waste liquid is reused, saving water resources.

[0031] 8. The pressurized entrained flow gasification system with a solid powder pump provided by the present invention has a Venturi desuperheater as the cooling unit. The water inlet port of the Venturi desuperheater is connected to the first liquid supply pipeline through the second liquid supply pipeline, and the connection point forms a second node. The liquid pump is located between the second node and the scrubbing tower. The raw syngas enters the chamber of the Venturi desuperheater for diffusion and deceleration. The liquid in the second liquid supply pipeline enters the chamber of the Venturi desuperheater through the water inlet port, and is fully mixed with the raw syngas, absorbing the heat in the raw syngas, thereby reducing the heat of the raw syngas, and then they are jointly discharged into the scrubbing tower. Such a setting can further recycle the liquid after scrubbing in the scrubbing tower, further saving water resources. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the drawings required for the description of the specific embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0033] Figure 1 It is a schematic structural diagram of the pressurized entrained flow gasification system with a solid powder pump according to an embodiment of the present invention;

[0034] Figure 2 It is a flow chart of the pressurized entrained flow gasification process according to an embodiment of the present invention.

[0035] Description of the reference numerals:

[0036] 1. Preparation unit; 11. Grinding device; 111. Feeding channel; 112. Solid raw material; 113. Inert gas; 12. Powder bin; 121. Second gas pipeline; 122. Loosening gas; 2. Gasifier; 21. Burner; 211. Spent fuel gas; 212. Medium-pressure oxygen; 22. Discharge slag lock hopper; 23. Coarse slag; 24. Drainage pipeline; 25. Quench chamber waste liquid; 3. Solid powder pump; 31. Feeding channel; 32. First gas pipeline; 33. High-pressure gas; 301. First node; 4. Cooling unit; 5. Scrubbing unit; 51. Scrubbing liquid inlet pipe; 61. First liquid supply pipeline; 62. Liquid pump; 63. Second liquid supply pipeline; 601. Second node; 7. Steam drum; 71. Circulating water pump; 72. Boiler feed water; 73. High-pressure steam; 8. Syngas. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0037] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0038] The pressurized entrained flow gasification system and process of solid powder pump provided in this embodiment can be applied to gasification reactions of combustibles such as pulverized coal, coal powder, and coke powder. Below, the devices, structures, and treatment processes provided in this embodiment will be described by taking the treatment of pulverized coal as an example.

[0039] Before introducing the pressurized entrained flow gasification system and process of solid powder pump provided in this embodiment, the traditional entrained flow gasification system will be described first. In the traditional entrained flow gasification system, the link for pressurized conveying of powder materials is usually completed by an atmospheric pressure pulverized coal bin, a pulverized coal lock hopper, and a pulverized coal feeding tank. Among them, the coordinated sequence control of the atmospheric pressure pulverized coal bin, the pulverized coal lock hopper, and the pulverized coal feeding tank is also required to proceed. Specifically, in the feeding process of the atmospheric pressure pulverized coal bin, the channel between the pulverized coal lock hopper and the pulverized coal feeding tank needs to be closed, and the channel between the atmospheric pressure pulverized coal bin and the pulverized coal lock hopper needs to be opened. The pulverized coal enters the pulverized coal lock hopper under the action of gravity. Then, high-pressure carbon dioxide or nitrogen is filled into the pulverized coal lock hopper for pressurization. After the pressure in the tank of the pulverized coal lock hopper reaches the specified value, the channel between the pulverized coal lock hopper and the pulverized coal feeding tank is opened. Under the action of the pressure difference, the pulverized coal in the pulverized coal lock hopper enters the pulverized coal feeding tank. Then, the channel between the pulverized coal lock hopper and the pulverized coal feeding tank is closed, and the pulverized coal lock hopper is depressurized to ensure that the next pulverized coal can enter the pulverized coal lock hopper under the action of gravity. Thus, one pulverized coal conveying link is completed. It can be seen that the traditional pulverized coal conveying method not only has a complex structure, but also requires complex sequence control to proceed, and its conveying process cannot be continuous, resulting in low gasification reaction efficiency. Moreover, the frequent depressurization of the pulverized coal lock hopper and the pulverized coal feeding tank will waste a large amount of gas resources. Although the number of pulverized coal feeding tanks has been increased in some technical improvements, the problems of non-continuous conveying of pulverized coal and waste of gas resources inherent in it have not been solved.

[0040] As Figure 1 shown, to solve the above problems, this embodiment provides a pressurized entrained flow gasification system of solid powder pump, including: a preparation unit 1, a gasifier 2, and a solid powder pump 3.

[0041] The preparation unit 1 is used for preparing and storing powder materials. Among them, the powder materials are stored in the form of a gas-solid mixture, and the powder materials can be pulverized coal.

[0042] The gasifier 2 includes an inlet and an outlet. The gasifier 2 further includes a reaction chamber, a quench chamber, and a slag discharge port. The reaction chamber serves as the main place for the gasification reaction of pulverized coal. The quench chamber is used to cool the molten slag after the reaction of the pulverized coal. The slag discharge port is used to discharge the molten slag for subsequent treatment. For example, a slag discharge lock hopper 22 can be provided downstream of the slag discharge port, and the slag discharge lock hopper 22 discharges the coarse slag 23.

[0043] The solid powder pump 3 is connected between the preparation unit 1 and the inlet of the gasifier 2 through a feeding channel 31, and is adapted to continuously transport the powder of the preparation unit 1 to the gasifier 2. That is, the solid powder pump 3 continuously transports the gas-solid mixture to the inlet of the gasifier 2 in a form similar to fluid transportation, ensuring that the reaction of the powder in the gasifier can proceed continuously and improving the gasification efficiency.

[0044] In this embodiment, the powder is stored in the form of a gas-solid mixture, making the powder fluid. Then, the powder is continuously transported through the inlet to the gasifier 2 by the downstream solid powder pump 3. The gasifier 2 converts the powder into raw syngas through the gasification reaction and discharges it from the outlet. Compared with the traditional entrained flow gasification system, there is no need to set up a single or multiple feeding tanks, which simplifies the structure and also omits cumbersome operation steps such as feeding, pressurization, discharging, and depressurization. It ensures the continuity of the transportation of the solid raw material 112 and improves the working efficiency of the entrained flow gasification system. The solid powder pump 3 in this embodiment does not need to perform frequent depressurization operations, thus saving gas resources.

[0045] At the same time, since the powder is stored in the preparation unit 1 in the form of a gas-solid mixture, combined with the fluidity of the gas-solid mixture, the powder in the preparation unit 1 can be transported to the gasifier 2 for reaction by the solid powder pump in the form of dry powder dense-phase transportation. The solid powder pump can transport at a high pressure of more than 6.5 MPa and can also operate stably in high-temperature and high-pressure environments, ensuring the continuity, efficiency, and reliability of the transportation process.

[0046] In addition, the feeding tank of the traditional entrained flow gasification system will have the problem of uneven raw material supply, which leads to fluctuations in gasification efficiency or reaction interruption. In contrast, by the method of transporting the gas-solid mixture by the solid powder pump, it can ensure that the gas-solid mixture continuously, stably, and evenly enters the gasifier 2, thus ensuring the stability of the gasification reaction.

[0047] The solid powder pump in this embodiment can be a positive displacement pump such as a rotary valve type, a screw type, or a double-chamber type, and transports the gas-solid mixture containing powder through the change of the volume in the pump cylinder of the above positive displacement pump.

[0048] For example, a rotary valve positive displacement pump mainly uses a rotary valve to control the entry and conveyance of powder materials. Its core conveyance method is to convey powder materials through rotating blades and rely on pneumatic force or gravity to complete the transportation. In the feeding stage, the powder materials enter the feeding chamber of the rotary valve from the powder bin 12 or the hopper. The rotary valve blades rotate, gradually filling the powder materials into the blade grooves. In the conveyance stage, the rotary valve blades rotate, gradually feeding the powder materials into the conveyance pipeline. In the discharging stage, the powder materials at the outlet of the rotary valve enter the feeding channel 31 and then enter the gasifier 2.

[0049] A screw positive displacement pump uses the rotation of screw blades to push powder materials to convey along the pipeline, similar to the mechanical conveyance method. In the feeding stage, the powder materials fall from the powder bin 12 into the screw conveyance cavity and enter the conveyance channel through gravity or auxiliary air flow. In the conveyance stage, the screw blades rotate, and the powder materials move between the blades and are pushed towards the discharge port. During the conveyance process, the conveyance rate of the powder materials can be controlled by adjusting the rotation speed of the screw blades. In the discharging stage, the powder materials are pushed to the feeding channel 31 and then enter the gasifier 2.

[0050] A double-chamber positive displacement pump conducts high-pressure conveyance in a pulsed manner through two alternately working conveyance cavities to ensure the stable supply of powder materials. In the feeding stage, the powder materials enter the first conveyance chamber from the powder bin 12, and the discharge valve is closed to prevent powder material leakage. At the same time, the powder materials filled in the previous round are being conveyed out through the second conveyance chamber. In the pressurized conveyance stage, the pressure in the first conveyance chamber gradually increases. After reaching the set value, the discharge valve is opened, and the powder materials are pushed to the conveyance pipeline under the action of high pressure. At the same time, the second conveyance chamber starts to feed to ensure the continuity of conveyance. Thus, they cycle alternately. After the first chamber completes discharging, it enters the re-feeding stage, and the second chamber enters the pressurized conveyance stage. The two chambers operate alternately to ensure the uninterrupted conveyance of powder materials. The second conveyance chamber conveys the powder materials into the feeding channel 31 and then enters the gasifier 2.

[0051] To clearly illustrate the advantages of using a solid powder pump to convey powder materials in this embodiment, the applicant takes the solid powder pump conveyance as the experimental group and the traditional gas pressurized conveyance as the control group, and uses the conveyance medium requirements and resource consumption during the working process as reference data to obtain the following experimental data:

[0052]

[0053] In the gasification reaction, the higher the gasification pressure, the higher the reaction efficiency. This experiment mainly takes two reaction pressures of 4.0 MPag and 6.5 MPag for the gasification pressure as examples for illustration.

[0054] When the gasification pressure is 4.0 MPag, the oxygen pressure requirement in the gasifier 2 is 5.2 MPag. In the upstream transportation process, when using a solid powder pump for transportation, the inert gas pressure requirement is 5.4 MPag. Taking carbon dioxide CO2 as an example of the inert gas, the compression work of the inert gas is less than or equal to 1300 kw, there is no need to discharge the inert gas, and the investment is less than 20 million yuan. When using traditional gas pressurized transportation, the pressure requirement of the inert gas is greater than or equal to 7.3 MPag. At least 15000 Nm3 / h of CO2 needs to be pressurized to 7.3 MPag. The compression work of the inert gas is 2600 kW. Due to the need for pressure relief, the discharge amount of the inert gas is greater than 10000 Nm3 / h, and an additional gas compression work of 2200 kW is required. The investment is greater than 85 million yuan.

[0055] When the gasification pressure is 6.5 MPag, the oxygen pressure requirement in the gasifier 2 is 7.7 MPag. In the upstream transportation process, when using a solid powder pump for transportation, the inert gas pressure requirement is 7.9 MPag. Taking carbon dioxide CO2 as an example of the inert gas, the compression work of the inert gas is less than or equal to 1600 kW, there is no need to discharge the inert gas, and the investment is less than 30 million yuan. When using traditional gas pressurized transportation, the pressure requirement of the inert gas is greater than or equal to 9.0 MPag. The compression work of the inert gas is 3100 kW. Due to the need for pressure relief, the discharge amount of the inert gas is greater than 11000 Nm3 / h, and an additional gas compression work of 2200 kW is required. The investment is greater than 85 million yuan.

[0056] It can be seen that the transportation method through the solid powder pump can not only save more than 50% of the power consumption, but also reduce the gas consumption and the investment cost.

[0057] Considering that the gasification reaction of the powder in the gasifier 2 has high-pressure requirements, as Figure 1 shown, a first gas pipeline 32 is connected to the feeding channel 31 of this embodiment to form a first node 301. The first node 301 is located between the solid powder pump and the gasifier 2. The first gas pipeline 32 is suitable for introducing high-pressure gas 33 into the feeding channel 31. The high-pressure gas 33 can be high-pressure nitrogen or high-pressure carbon dioxide gas. When the powder leaves the solid powder pump in the form of a gas-solid mixture and enters the downstream, it can be mixed with the high-pressure gas 33 and enter the gasifier 2 together with the high-pressure gas 33. On the one hand, the high-pressure gas 33 can further provide the transportation power. On the other hand, the high-pressure gas 33 can be pressurized to ensure that the powder enters the gasifier 2 under high-pressure conditions, further ensuring the continuous transportation of the powder and the gasification efficiency of the powder in the reaction furnace.

[0058] As Figure 1As shown, in this embodiment, the preparation unit 1 includes a powder grinding device 11 and a powder bin 12. The powder grinding device 11 is communicated with the feed inlet of the powder bin 12 through a feeding channel 111. The discharge outlet of the powder bin 12 is communicated with the feeding channel 31. Among them, the powder prepared by the powder grinding device 11 is transported to the feeding channel 111 through gas. For example, a feeding port is provided on the powder grinding device 11 for adding a solid raw material 112. An air inlet is provided at the discharge end of the powder grinding device 11, and the air inlet is communicated with an external gas pipeline. The gas pipeline is suitable for introducing a low-pressure inert gas such as low-pressure nitrogen. The low-pressure nitrogen will not react with the powder, and can drive the powder to enter the powder bin through the feeding channel 111, and is mixed with the powder to form a gas-solid mixture and stored in the powder bin 12 together.

[0059] The specific form of the powder grinding device 11 is not limited. It may include a grinding structure and a screen structure. The grinding structure grinds the solid raw material, and the screen structure filters the raw materials with larger particle sizes. For example, a 200-mesh screen can be selected for the screen structure. Thus, the solid raw material 112 is ground into powder with a particle size meeting the requirements by the powder grinding device 11, and then the powder is transported to the powder bin 12 through the feeding channel 111 in the form of gas transportation. Feeding in the form of gas transportation allows the powder to be stored in the powder bin 12 in the form of a gas-solid mixture, so as to facilitate the subsequent transfer of the powder to the gasifier 2 through a solid powder pump. Compared with the traditional elevator, conveyor belt or hoist, such a setting not only simplifies the transportation structure between the powder grinding device 11 and the powder bin 12, but also can omit the subsequent step of converting the powder into a fluid gas-solid mixture.

[0060] Considering that some powder will inevitably settle in the powder bin 12, as Figure 1 shown, in this embodiment, a second gas pipeline 121 is provided at the discharge outlet of the powder bin 12. The second gas pipeline 121 is suitable for intermittently introducing a loosening gas 122 into the discharge outlet. The loosening gas 122 can be low-pressure nitrogen.

[0061] Since the powder is stored in the powder bin 12 in the form of a gas-solid mixture, and the bottom of the powder bin 12 is usually designed with a reduced opening, after the gas-solid mixture in the powder bin 12 settles, it is inevitable that the powder will agglomerate or accumulate at the discharge outlet at the bottom of the powder bin 12. Therefore, the loosening gas 122 can be intermittently introduced into the discharge outlet through the second gas pipeline 121. For example, a period for introducing the loosening gas 122 is set. The loosening gas 122 can loosen the powder accumulated or agglomerated at the discharge outlet, or blow it to move along the side wall of the bottom of the powder bin 12, so that the powder returns to the state of a gas-solid mixture again, avoiding blocking the discharge outlet and ensuring that the downstream solid powder pump can efficiently, continuously and stably transport the powder to the gasifier 2.

[0062] In this embodiment, the gas introduced into the first gas pipeline 32 and the second gas pipeline 121 is one of nitrogen, carbon dioxide, carbon monoxide, hydrogen, methane, and superheated steam, or a mixture of two or more of these gases. Methane can be natural gas or gas.

[0063] As Figure 1 shown, in this embodiment, the inlet of the gasifier 2 is connected to the feeding channel 31 through the burner 21. The burner 21 is provided with a first feeding port and a second feeding port. The burner 21 can be an industrial burner. The first feeding port is adapted to introduce spent fuel gas 211 into the burner 21, and the second feeding port is adapted to introduce medium-pressure oxygen 212 into the burner 21. By respectively adding the spent fuel gas 211 and the medium-pressure oxygen 212 through the first feeding port and the second feeding port, the spent fuel gas 211 and the medium-pressure oxygen 212 can be mixed, and driven by the gas-solid mixture containing powder, enter the reaction chamber of the gasifier 2 at high speed. Compared with directly introducing the spent fuel gas 211 and the medium-pressure oxygen 212 into the reaction chamber respectively, such a setting can ensure the uniform mixing of the spent fuel gas 211 and the medium-pressure oxygen 212, provide an oxidant and heat for the reaction in the reaction furnace, and promote the reaction in the reaction chamber. Both the spent fuel gas 211 and the medium-pressure oxygen 212 can be used as oxidants. Such a setting can realize the reuse of the spent fuel gas 211 and further save resources.

[0064] As Figure 1 shown, in this embodiment, the pressurized entrained flow gasification system for solid powder also includes a cooling unit 4 and a washing unit 5, and the cooling unit 4 and the washing unit 5 are sequentially connected downstream of the outlet of the gasifier 2.

[0065] The cooling unit 4 can cool the raw syngas from the gasifier 2, and the cooled raw syngas enters the washing unit 5 for washing to remove impurities, particulate matter, and some acidic gases in the raw syngas. The finally output syngas can enter the subsequent chemical production or fuel utilization stage.

[0066] As Figure 1 shown, in an implementation manner of this embodiment, the washing unit 5 is a washing tower, and the washing tower is connected to the quench chamber water inlet of the gasifier 2 through a first liquid supply pipeline 61, and a liquid pump 62 is provided on the first liquid supply pipeline 61. As an alternative implementation manner, it can also be that the washing unit 5 can also be a packed tower.

[0067] A washing liquid inlet pipe 51 is provided on the washing tower. The washing liquid inlet pipe 51 can supply water to the atomizing nozzles inside the washing tower. The atomizing nozzles remove impurities, particulate matters and some acidic gases in the raw syngas by spraying. After being washed, the raw syngas can be used as syngas 8 for downstream processes. In addition, the liquid that has washed the raw syngas can be pumped into the quench chamber water inlet of the gasifier 2 by a liquid pump 62. The quench chamber drain can cool the molten slag generated in the gasifier 2 to form solid coarse slag for subsequent discharge treatment. Passing the liquid washed in the washing tower into the quench chamber through the liquid pump 62 reuses the waste liquid and saves water resources.

[0068] In this embodiment, a drain pipe 24 is connected to the outlet of the quench chamber. The drain pipe 24 is used to discharge the quench chamber waste liquid 25. The quench chamber waste liquid 25 can be reused after processes such as sedimentation and filtration.

[0069] As Figure 1 shown, in an implementation manner of this embodiment, the cooling unit 4 is a Venturi desuperheater. The water inlet port of the Venturi desuperheater is connected to the first supply pipe 61 through a second supply pipe 63, and the connection point forms a second node 601. The liquid pump 62 is located between the second node 601 and the washing tower. The raw syngas enters the chamber of the Venturi desuperheater for diffusion and deceleration. The liquid in the second supply pipe 63 enters the chamber of the Venturi desuperheater through the water inlet port and is fully mixed with the raw syngas, absorbing the heat in the raw syngas, thereby reducing the heat of the raw syngas, and then they are jointly discharged into the washing tower. Such a setting can further reuse the liquid washed in the washing tower and further save water resources. As an alternative implementation manner, the cooling unit 4 can also be a cooling tower.

[0070] As Figure 1 shown, in this embodiment, the gasifier 2 can also include a sandwich layer. The sandwich layer adopts a water-cooled wall structure with flowing water or steam inside. While protecting the furnace chamber, the generated steam can also be used for external heating to improve resource utilization rate. As an alternative implementation manner, the gasifier 2 may not be provided with a sandwich layer.

[0071] As Figure 1As shown, in an implementation manner of this embodiment, a liquid inlet and a steam outlet are provided in the interlayer of the gasifier 2. The pressurized entrained flow gasification system with a solid powder pump further includes a steam drum 7. The riser pipe of the steam drum 7 is communicated with the steam outlet of the gasifier 2, and the downcomer pipe of the steam drum 7 is communicated with the liquid inlet of the gasifier 2. A circulation pump may be provided on the downcomer pipe. A high-pressure steam outlet pipe and a boiler feed water inlet pipe are further provided on the steam drum 7. The boiler feed water 72 enters the steam drum 7 through the boiler feed water inlet pipe, and then enters the interlayer of the gasifier 2 through the downcomer pipe. The water vapor in the interlayer of the gasifier 2 enters the steam drum 7 through the riser pipe, and becomes high-pressure steam 73 after superheating and is discharged from the high-pressure steam outlet pipe. The high-pressure steam 73 can be used for external heating or thermodynamic work to improve the resource utilization rate.

[0072] As Figure 2 shown, this embodiment provides a pressurized entrained flow gasification process with a solid powder pump for the above-mentioned pressurized entrained flow gasification system with a solid powder pump. The pressurized entrained flow gasification process with a solid powder pump includes:

[0073] Step S1: The preparation unit 1 prepares and stores the powder. The preparation unit 1 includes a powder grinding device 11 and a powder bin 12. The powder grinding device 11 is communicated with the feed inlet of the powder bin 12 through a feeding channel 111, and the discharge outlet of the powder bin 12 is communicated with a feeding channel 31. Among them, the powder prepared by the powder grinding device 11 is transported to the feeding channel 111 through gas.

[0074] Step S2: The solid powder pump 3 continuously pressurizes and transports the powder in the preparation unit 1 into the gasifier 2.

[0075] Step S3: The gasifier 2 converts the powder into raw syngas through a gasification reaction. The inlet of the gasifier 2 is communicated with the feeding channel 31 through a burner 21. The side wall of the burner 21 is provided with a first feeding port and a second feeding port. The first feeding port is suitable for introducing spent fuel gas 211 into the burner 21, and the second feeding port is suitable for introducing medium-pressure oxygen 212 into the burner 21. By respectively adding the spent fuel gas 211 and the medium-pressure oxygen 212 through the first feeding port and the second feeding port, the spent fuel gas 211 and the medium-pressure oxygen 212 can be mixed, and under the drive of the gas-solid mixture containing the powder, they enter the reaction chamber of the gasifier 2 at a high speed. Compared with directly introducing the spent fuel gas 211 and the medium-pressure oxygen 212 into the reaction chamber respectively, such a setting can ensure the uniform mixing of the spent fuel gas 211 and the medium-pressure oxygen 212, provide an oxidant and heat for the reaction in the reaction furnace, promote the reaction in the reaction chamber, and the powder generates raw syngas through a gasification reaction in the reaction chamber.

[0076] In addition to the above steps, it further includes:

[0077] The cooling unit 4 cools the raw syngas and sends it to the washing unit 5. The cooling unit 4 is a Venturi attemperator.

[0078] The washing unit 5 washes the cooled raw syngas to obtain syngas 8. The washing unit 5 is a washing tower.

[0079] The above process flow was synchronously described when introducing the pressurized entrained flow gasification system with a solid powder pump in the foregoing text. Those skilled in the art can learn from the foregoing description the beneficial effects of using a solid powder pump to transport powders, and thus no repeated description will be given here.

[0080] Although the embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations all fall within the scope defined by the appended claims.

Claims

1. A pressurized entrained flow gasification system for solid powder pumps, characterized in that, Comprising: A preparation unit (1) for preparing and storing powder materials, wherein the powder materials are stored in the form of a gas-solid mixture; A gasifier (2) including an inlet and an outlet; A solid powder pump (3) connected between the preparation unit (1) and the inlet of the gasifier (2) through a feeding channel (31), adapted to continuously pressurize and convey the powder materials of the preparation unit (1) to the gasifier (2).

2. The pressurized entrained flow gasification system of a solid powder pump according to claim 1, wherein The preparation unit (1) includes a powder grinding device (11) and a powder bin (12). The powder grinding device (11) is communicated with the feeding port of the powder bin (12) through a feeding channel (111), and the discharging port of the powder bin (12) is communicated with the feeding channel (31). Among them, the powder materials prepared by the powder grinding device (11) are conveyed to the feeding channel (111) through gas.

3. The pressurized entrained flow gasification system of a solid powder pump according to claim 2, wherein A second gas pipeline (121) is provided at the discharging port of the powder bin (12), and the second gas pipeline (121) is adapted to intermittently introduce a loosening gas (122) into the discharging port.

4. The pressurized entrained flow gasification system of a solid powder pump according to claim 3, wherein A first gas pipeline (32) is connected to the feeding channel (31). The connection point of the feeding channel (31) and the first gas pipeline (32) forms a first node (301). The first node (301) is located between the solid powder pump (3) and the gasifier (2). The first gas pipeline (32) is adapted to introduce high-pressure gas (33) into the feeding channel (31).

5. The pressurized entrained flow gasification system of the solid powder pump according to claim 4, characterized in that The gases introduced into the first gas pipeline (32) and the second gas pipeline (121) are one of nitrogen, carbon dioxide, carbon monoxide, hydrogen, methane, and superheated steam, or a mixture of two or more of these gases.

6. The pressurized entrained flow gasification system of the solid powder pump according to claim 1, characterized in that, The inlet of the gasifier (2) is communicated with the feeding channel (31) through a burner (21). The burner (21) is provided with a first feeding port and a second feeding port. The first feeding port is adapted to introduce spent fuel gas (211) into the burner (21), and the second feeding port is adapted to introduce pressurized oxygen (212) into the burner (21).

7. The pressurized entrained flow gasification system of a solid powder pump according to claim 1 or 2, characterized in that It further includes a cooling unit (4) and a washing unit (5). The cooling unit (4) and the washing unit (5) are sequentially connected downstream of the outlet of the gasifier (2).

8. The pressurized entrained flow gasification system of a solid powder pump according to claim 7, characterized in that, The washing unit (5) is a washing tower. The washing tower is communicated with the water inlet of the quench chamber of the gasifier (2) through a first liquid supply pipeline (61). A liquid pump (62) is provided on the first liquid supply pipeline (61).

9. The pressurized entrained flow gasification system of a solid powder pump according to claim 8, characterized in that, The cooling unit (4) is a Venturi desuperheater. The water inlet port of the Venturi desuperheater is communicated with the first liquid supply pipeline (61) through a second liquid supply pipeline (63), and the connection point forms a second node (601). The liquid pump (62) is located between the second node (601) and the washing tower.

10. A pressurized entrained flow gasification process for solid powder pumps, which is used in the pressurized entrained flow gasification system for solid powder pumps according to any one of claims 1 to 9, characterized in that, The process includes: The preparation unit (1) prepares and stores powder materials; The solid powder pump (3) continuously pressurizes and conveys the powder materials in the preparation unit (1) into the gasifier (2); The gasifier (2) converts the powder materials into crude syngas through a gasification reaction.

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